Liquid containment door with continuous gasket

ABSTRACT

A pedestrian door system includes a door frame comprising a frame strike side, a frame hinge side, and a frame sealing surface that extends up each of the frame strike and frame hinge sides. A threshold extends between the frame strike and frame hinge sides and includes a base secured to a floor surface and a threshold sealing surface. A door panel includes a panel bottom side, a panel strike side, a panel hinge side, and a continuous gasket extending continuously along the panel bottom side and up each of the panel strike and panel hinge sides. A door hinge couples the panel hinge side to the frame hinge side and facilitates hinged movement of the door panel between an open position and a closed position in which the gasket seals against the frame sealing surface and the threshold sealing surface in a liquid-tight manner.

TECHNICAL FIELD

The disclosure relates to liquid-tight door systems.

BACKGROUND

In many instances, doors are generally used to separate one environmentfrom another. While this may be as simple as separating one room in abuilding from another, this may also include separating an interiorenvironment from an external environment that is subject to naturalelements, or separating an environment that is to be protected from anenvironment that includes a liquid that could be detrimental ifintroduced into the environment that is to be protected. These doors cantypically be in either a closed position, where the separation isintended to be in place by the presence of the door blocking passagefrom one environment to the other, or an open position, where passage ispermitted through the area outlined by the frame of the door.

While doors in a closed position generally do an adequate job ofpreventing large, solid objects from passing from an environment on oneside of the door panel to an environment on the other side of the doorpanel, the mechanics of a door opening and closing create issues withthe prevention of liquid from passing through the open crevices of thedoor system, even when the door is in the closed position. For instance,the presence of hinges on the door and the need for the door panels toswing open and closed typically prevent formation of a liquid-tightseal, as the hinges space the door panels away from the frame, and adoor must be spaced away from the floor such that the door does notscrape the floor as it moves between open and closed positions. Examplesof when it is desirable to prevent liquid from passing through opencrevices of a closed door include floods and liquid spills. This problemis only compounded with double doors, where there are two door panelsthat swing away from one another and latch either together or into acommon center structure.

SUMMARY

In general, the disclosure describes a liquid containment barrier or aliquid containment door (hereinafter referred to collectively as a“liquid containment door”). A liquid containment barrier/door isdesigned in such a way that a continuous gasket system is installed ontothe door panel to make a continuous length of gasket to create aliquid-tight seal between the door panel and threshold, and between thedoor panel and frame, up to the designed water protection level. Thecontinuous gasket system may be a single gasket piece or multiple gasketpieces connected to one another.

In some instances, the liquid containment door may also be implementedinto a door system with a low threshold. The low threshold has thebenefit of allowing traffic through the doorway, such as foot traffic,carts, vehicles, or wheelchairs with little impedance. Low thresholdsare generally preferred and often required by regulations, such as theAmericans with Disabilities Act (“ADA”), which detail specificdimensional requirements of the threshold size and shape. The continuouslength of gasket attached to the door panel allows the door panel tocreate a liquid-tight seal to the perimeter door frame (two verticaljambs and header) and across the bottom of the door where the gasketmakes a seal to a low profile threshold (e.g., an ADA-compliantthreshold). An additional benefit of the continuous gasket beingattached to the door panel and not attached to the threshold is that thegasket is not exposed to damage by traffic through the doorway.

The liquid containment door can function as a normal use pedestriandoor. Examples of pedestrian doors include walk doors, personnel doors,passage doors, entry doors, entrance doors, accessible entrance orpassage doors, handicap accessible doors, and exit doors. The liquidcontainment door can perform as a flood barrier or a spill containmentsystem or can perform any other similar function when in the closed andlatched position. Further, the liquid containment door may beimplemented into any other type of door system, such as a verticallyhinged door system, a sliding door system, a double door system, aFrench door system, an automatic door system, a rotating door system, orany other door system that may move between open and closed positions.

In one example, the disclosure is directed to a pedestrian door systemthat includes a door frame comprising a frame strike side, a frame hingeside, and a frame sealing surface that extends at least partially upeach of the frame strike side and the frame hinge side. The pedestriandoor system further includes a threshold configured to extend betweenthe frame strike side and the frame hinge side, the threshold includinga base configured to be secured to a floor surface and a thresholdsealing surface, wherein the threshold has an overall height of nogreater than 20 millimeters. The pedestrian door system also includes adoor panel comprising a panel bottom side, a panel strike side, a panelhinge side, and a continuous gasket extending continuously along thepanel bottom side and at least partially up each of the panel strikeside and the panel hinge side. The pedestrian door system furtherincludes a door hinge configured to hingedly couple the panel hinge sideof the door panel to the frame hinge side of the door frame and tofacilitate hinged movement of the door panel relative to the door framebetween an open position and a closed position in which the continuousgasket of the door panel seals against the frame sealing surface of thedoor frame and against the threshold sealing surface of the threshold ina liquid-tight manner.

In another example, the disclosure is directed to a door system thatincludes a door frame comprising a frame first side, a frame secondside, and a frame sealing surface that extends at least partially upeach of the frame first side and the frame second side. The door systemfurther includes a threshold configured to extend between the framefirst side and the frame second side, the threshold including a baseconfigured to be secured to a surface and a threshold sealing surface.The door system also includes a door panel comprising a panel bottomside, a panel first side, a panel second side, and a panel sealingsurface that extends along the panel bottom side and at least partiallyup each of the panel first side and the panel second side. The doorsystem further includes a gasket that comprises a bulb-type gasket withholes defined in a wet side wall of the gasket, the holes beingconfigured to receive liquid and/or air into an interior space withinthe bulb-type gasket. The door panel is movable relative to the doorframe between an open position and a closed position in which the gasketis positioned between the panel sealing surface of the door panel andthe frame sealing surface of the door frame and between the panelsealing surface of the door panel and the threshold sealing surface ofthe threshold to create a liquid-tight seal.

In another example, the disclosure is directed to a door system thatincludes a door frame comprising a frame strike side, a frame hingeside, and a frame sealing surface that extends at least partially upeach of the frame strike side and the frame hinge side. The door systemfurther includes a threshold configured to extend between the framestrike side and the frame hinge side, the threshold including a baseconfigured to be secured to a floor surface and a threshold sealingsurface, wherein the threshold has an overall height of no greater than20 millimeters. The door system also includes a door panel comprising apanel bottom side, a panel strike side, a panel hinge side, and acontinuous gasket extending continuously along the panel bottom side andat least partially up each of the panel strike side and the panel hingeside. The door system further includes a door hinge configured tohingedly couple the panel hinge side of the door panel to the framehinge side of the door frame and to facilitate hinged movement of thedoor panel relative to the door frame between an open position and aclosed position in which the continuous gasket of the door panel sealsagainst the frame sealing surface of the door frame and against thethreshold sealing surface of the threshold in a liquid-tight manner.

The details of one or more examples of the disclosure are set forth inthe accompanying drawings and the description below. Other features,objects, and advantages of the disclosure will be apparent from thedescription and drawings, and from the claims.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective view of a door frame configured in accordancewith one or more aspects of this disclosure.

FIG. 2A is a perspective view of various frame surfaces configured inaccordance with one or more aspects of this disclosure.

FIG. 2B is a schematic cross-sectional view of a door panel and doorframe as configured in accordance with one or more aspects of thisdisclosure.

FIG. 2C is a schematic cross-sectional view of a door panel and doorframe as configured in accordance with one or more aspects of thisdisclosure.

FIG. 3 is a wet-side view of a door panel as configured in accordancewith one or more aspects of this disclosure.

FIG. 4 is a view of a door panel and a door frame configured inaccordance with one or more aspects of this disclosure.

FIG. 5 is a dry-side view of a continuous gasket, a door panel, and adoor frame configured in accordance with one or more aspects of thisdisclosure.

FIG. 6 is a perspective view of a continuous gasket attached to a doorpanel and configured in accordance with one or more aspects of thisdisclosure.

FIG. 7 is a perspective view of a door system that includes a doorpanel, a continuous gasket, and a threshold, each configured inaccordance with one or more aspects of this disclosure.

FIGS. 8A-8B are section views of a door system that includes a doorpanel, a continuous gasket, and a threshold, each configured inaccordance with one or more aspects of this disclosure.

FIGS. 9A-9C are top section views of a door system that includes ahinge, a door panel, a continuous gasket, and a threshold, eachconfigured in accordance with one or more aspects of this disclosure.

FIG. 10 is a perspective view of a hinge of a door system configured inaccordance with one or more aspects of this disclosure.

FIG. 11 is a perspective view of a door system that includes two doorpanels, a center post, and a door frame, each configured in accordancewith one or more aspects of this disclosure.

DETAILED DESCRIPTION

In general, the disclosure describes a liquid containment barrier or aliquid containment door (hereinafter referred to collectively as a“liquid containment door”). A liquid containment door is designed insuch a way that a continuous gasket system is installed onto the doorpanel to make a continuous length of gasket to create a liquid-tightseal between the door panel and threshold, and between the door paneland frame, up to the designed water protection level. The continuousgasket system may be a single gasket piece or multiple gasket piecesconnected to one another. This disclosure may, in referencing the liquidcontainment aspects of the door referenced herein, use terminologyrelated to “flooding.” However, the application of the techniques andobjects of this disclosure can extend beyond flood protection to suchproducts as spill containment, or containment of any liquid. Thisdisclosure may also refer to the application of the continuous gasket toa typical pedestrian or walk door, but examples of this disclosure canbe applied to any type of door that hinges along its vertical side.Further, the continuous gasket described herein can be applied to anynumber of doors, including personnel doors, passage doors, entry doors,entrance doors, accessible entrance or passage doors,handicap-accessible doors, pedestrian doors, exit doors, or any othertype of door that includes a threshold and frame as described herein. Insome instances, door systems disclosed herein may not be for apedestrian use, but for use with larger doors, such as stadium entriesor entries to large commercial buildings.

As a preliminary note, it should be recognized that the various figuresaccompanying this application depict various parts of the overall doorsystem. It should also be recognized that any individual figure may showonly a certain subset of the features of the overall door systemdescribed herein. As such, when similar structures are described indifferent figures, it should be understood that those structures areinterchangeable with the similarly named structures in other ones ofFIGS. 1-11. Further, it should be understood that any of FIGS. 1-11 canbe combined when analyzing how the figures fit together. For instance,door frame 100 may include frame strike side 102 and frame hinge side104, which may be equivalent to frame strike side 402 and frame hingeside 404, respectively, which frame door panel 418, which may beequivalent to door panel 818. As such, when describing gasket 838 beinginstalled on door panel 818, it should be understood that gasket 838 canalso be present on door panel 418, although not shown, and that doorpanel 818 can be installed on door frame 100, although not shown. Inother instances, each of FIGS. 1-11 may be interpreted in a standalonefashion, as there may be differences in some of the structures betweenFIGS. 1-11 (e.g., FIG. 4 depicting a single door system and FIG. 11depicting a double door system).

FIG. 1 illustrates a door frame 100 configured in accordance with one ormore aspects of this disclosure. Door frame 100 outlines a hole in wall110. By including a hole in wall 110, objects and living beings are ableto pass through wall 110 from one environment on a first side of wall110 to a second environment on a second side of wall 110. Door frame 100may also be configured to receive a door panel, such as door panel 418of FIG. 4, door panel 518 of FIG. 5, or door panel 818 of FIG. 8. Whendoor frame 100 includes a door panel, a user of the door panel may movethe door from an open position, where objects and living beings aretypically allowed to pass through the hole in wall 110, to a closedposition, where objects and living beings are typically blocked frompassing through the hole in wall 110. Door frame 100, as well as allparts of door frame 100 (e.g., frame strike side 102, frame hinge side104, frame top side 106), may be made of any material suitable for thefunctions of the door frame described herein, including wood, metal,plastic, rubber, or any combination thereof.

Door frame 100 includes frame hinge side 104. Frame hinge side 104typically attaches to the door panel using one or more hinges at variousheights. The one or more hinges enable the door panel to hingedly rotatearound frame hinge side 104 between open and closed positions.

Door frame 100 also includes frame strike side 102. Frame strike side102 typically includes at least a part of a latching mechanism (e.g.,latching mechanism 434 of FIG. 4). One or more parts of the overalllatching mechanism may also be attached to the door panel installed inthe door frame. The inclusion of the latching mechanism enables the doorpanel to remain in the closed position unless some predetermined amountof force in a particular direction is applied to the door panel or aportion of the door panel (e.g., a handle of the door panel). In someinstances, frame strike side 102, either alone or in combination withone or more of frame top side 106 and frame hinge side 104, may preventthe door panel from hingedly rotating past a certain point, such as thepoint where the latching mechanism is enabled. This may be accomplishedby frame strike side 102 extending away from door frame 100 and into therotational path of the door panel and frame hinge side 104 (see, e.g.,frame sealing surface 214 and stop surface 216 of FIG. 2A).

Door frame 100 also includes frame top side 106. Frame top side 106 maybe located at some portion of wall 110 that is lower than the highestpoint on wall 110, or frame top side 106 may be aligned with the highestpoint on wall 110 In some instances, similarly to frame strike side 102,frame top side 106 may extend away from door frame 100 to prevent thedoor panel from hingedly rotating past a certain point.

The hole created in wall 110 may also create floor surface 108 at thebottom of the hole. In some instances, floor surface 108 may be part ofdoor frame 100, while in other instances, floor surface 108 may be partof the building in which wall 110 is located.

FIG. 2A illustrates various frame surfaces of door frame 200, configuredin accordance with one or more aspects of this disclosure. In otherwords, FIG. 2A provides a zoomed-in perspective of a portion of doorframe 200, which may be similarly constructed and have similar featuresto door frame 100 of FIG. 1.

In the example of FIG. 2A, door frame 200 includes frame base 212. Framebase 212 may sit atop a floor surface (e.g., floor surface 108 of FIG.I) and provide a template for installing a threshold (e.g., threshold736 of FIG. 7) into door frame 200. Frame base 212 includes hole 218,which may be designed to receive an anchor bolt to secure the thresholdto frame base 212 and into the floor surface underneath frame base 212.Frame base 212 may not be present in all door systems. Instead, someinstances may include the threshold being attached directly to the floorsurface without the presence of frame base 212.

The vertical structures (frame sealing surface 214 and stop surface 216)in door frame 200 may be either of the frame hinge side or the framestrike side (e.g., frame strike side 102 and frame hinge side 104 ofFIG. 1). In other words, both the frame hinge side and the frame strikeside of a door frame in accordance with the techniques of thisdisclosure may include a frame sealing surface and a stop surface, asshown in FIG. 2A. In some instances, the frame sealing surface 214 andframe stop surface 216 may be one surface that creates both the doorstop surface and the gasket sealing surface (surface 220 of FIG. 2B,surface 222 of FIG. 2C). In some such instances, the door panel may notinclude a flange, and the gasket (e.g., continuous bulb-type gasket) maybe attached directly to the dry side of the door panel (FIG. 2C).

Stop surface 216 may be a portion of either the frame hinge side or theframe strike side that extends away from door frame 200 and into thehole in the wall or building created by door frame 200. Stop surface 216is configured to restrict the movement of any door panel past stopsurface 216 such that the door panel can only rotate from a closedposition outward in one direction. Stop surface 216 may further bealigned in door frame 200 such that the door panel contacts stop surface216, or is proximate to stop surface 216 (e.g., within 5 millimeters),when the latching mechanism of the frame strike side and/or the doorpanel is engaged to keep the door panel in a closed position.

Frame sealing surface 214 may be an additional portion of the framestrike side and/or frame hinge side that extends into the hole in thewall or building created by door frame 200. As shown, frame sealingsurface 214 is shorter in length than stop surface 216, meaning thatframe sealing surface 214 does not extend from door frame 200 into thehole in the wall created by door frame 200 as far as stop surface 216.This is because the door panel must be able to slide past frame sealingsurface 214 as the door panel moves between open and closed positions.When the door panel moves into the closed position, a gasket (e.g.,gasket 538 of FIG. 5 or gasket 838 of FIGS. 8A-8C) attached to the doorpanel, or the door panel itself, comes into contact with frame sealingsurface 214, creating a liquid-tight seal between the environment on oneside of the door panel and the environment on the second side of thedoor panel. In some instances, frame sealing surface 214 is made of thesame material as door frame 200 (e.g., wood, metal, plastic, rubber,some combination thereof, etc.). In other instances, frame sealingsurface 214 is a gasket itself, attaching to door frame 200 and theframe strike side or the frame hinge side, producing the liquid-tightseal with the door panel by coming into contact with the door panel whenthe door panel is in the closed position or by coming into contact withthe gasket installed on the door panel when the door panel is in theclosed position.

By being liquid-tight, the door system described herein may have zeroleakage, or may have some small amount of leakage or seepage. Oftenflood barrier manufacturers acknowledge that, even for doors consideredto be “watertight,” there may be a small leakage rate. Regardingflooding, the Federal Emergency Management Agency (FEMA) defines“watertight” as “substantially impermeable to the passage of water.”

FIG. 3 illustrates door panel 318 as configured in accordance with oneor more aspects of this disclosure. Door panel 318 may be installed in adoor frame, such as door frame 100 or door frame 200 of FIGS. 1 and 2,respectively. Door panel 318 may be made of any material suitable for adoor, including wood, plastic, metal, rubber, a combination thereof, orany other material. FIG. 3 shows the wet side of door panel 318, thoughin many configurations the dry side of door panel 318 also has a doorhandle.

Door panel 318 includes panel bottom side 320, panel strike side 322,and panel hinge side 324. Panel bottom side 320, when door panel 318 isin a closed position, may be situated over a threshold (e.g., threshold736 of FIG. 7). When door panel 318 rotates into the open position,panel bottom side 320 may swing above a floor surface that is below doorpanel 318.

Panel strike side 322 may be positioned to be on the same side of thedoor system as the frame strike side of the door frame that holds doorpanel 318 when door panel 318 is in the closed position. As such, panelstrike side 322 may also be the same side of door panel 318 as latchingmechanism 328. In the example of FIG. 3, latching mechanism 328 includesa rotatable handle that moves a mechanical latch inward into door panel318 when rotated. When the rotatable handle of latching mechanism 328 isnot moved, the mechanical latch remains protruding from door panel 318and into the frame strike side portion that holds the receiver of thelatching mechanism. This is merely one example of latching mechanism328, and any other latching mechanism known to be used for doors can beused in place of latching mechanism 328 shown in FIG. 3. As anotherexample, a multi-point vertical rod device may be used in which latchbolts engage into the header or the floor surface or both.

Panel hinge side 324 may be positioned to be on the same side of thedoor system as the frame hinge side of the door frame that holds doorpanel 318. As such, panel hinge side 324 may be on the same side of thedoor system as a door hinge. Door panel 318 may connect to the doorframe, or the wall that holds the door frame, via the door hinge. Thedoor hinge may be flexible, such that door panel 318 can hingedly rotatearound the door hinge to move between open and closed positions.

FIG. 4 illustrates a door panel 418 (opposite surface as shown in FIG.3) and door frame 400 configured in accordance with one or more aspectsof this disclosure. Door frame 400 may be similarly constructed, andmade of a similar material, as door frame 100 of FIG. 1 and/or doorframe 200 of FIG. 2A. Similarly, door panel 418 may be similarlyconstructed, and made of a similar material, as door panel 318 of FIG.3. FIG. 4 shows the dry side of door panel 418.

In the example of FIG. 4. door frame 400 includes frame strike side 402,frame hinge side 404, and frame top side 406. Door frame 400 may attachinto a wall or a building (not shown) using anchor bolts 430. While theexample of FIG. 4 shows 25 anchor bolts 430 to secure door frame 400into the wall or building, other examples may include more or feweranchor bolts. In some examples, other methods of attaching the doorframe to a wall may be used, such as welds, screws, bolts, concreteanchors, and so on.

Door panel 418 may also include panel bottom side 420, panel strike side422, panel hinge side 424, and panel top side 426. In some examples,door panel 418 may also include a gasket, such as gasket 538 of FIG. 5or gasket 838 of FIG. 8.

In some examples, the frame sealing surface (214 of FIG. 2A) may extendalong the entirety of frame strike side 402, frame top side 406, andframe hinge side 404. In other words, frame sealing surface may includethe entire extent of the opening within door frame formed by framestrike side 402, frame hinge side 404, and frame top side 406. In suchexamples, door panel 418 may further include a panel top side, and thegasket may extend continuously along the entirety of panel strike side422, panel top side 426, panel hinge side 424, and panel bottom side420. In other words, in this example, the gasket may be a continuousgasket that forms a full perimeter around door panel 418.

In some examples, the frame sealing surface (214 of FIG. 2A) may extendat least partially up each of the frame strike side 402 and the framehinge side 404. In this example, the gasket may be a continuous gasketthat extends along panel bottom side 420 and partially up each of panelstrike side 422 and panel hinge side 424 to provide a seal up to apredetermined liquid level. In some examples, the frame sealing surfacedoes not extend along the frame top side 406 (e.g., doors designed tofor liquid containment up to only a certain height).

As shown in FIG. 4, frame hinge side 404 and panel hinge side 424 arelocated on the same side of the door system. Similarly, frame strikeside 402 and panel strike side 422 are located on the same side of thedoor system. Panel strike side 422 and frame strike side 402 may alsoinclude portions of latching mechanism 434. For instance, door panel 418may include crash bar 432 (also commonly referred to as a push bar or apanic bar) situated in an offset manner such that it is closer to panelstrike side 422 rather than panel hinge side 424. When crash bar 432 ispressed inward towards door panel 418, latching mechanism 434 retractsinto door panel 418, enabling door panel 418 to be swung away from doorframe 400 around hinges on the opposite side of door panel 418 and onframe hinge side 404 and panel hinge side 424. This is merely oneexample of a handle and latching mechanism for operating door panel 418,and any other type of handle and/or latching mechanism system canreplace crash bar 432 and latching mechanism 434 of FIG. 4. In manyexamples, latching mechanism 434 may be a passive latching mechanismconfigured to hold door panel 418 in the closed position withoutseparate manual activation. In some examples, latching mechanism 434 maybe a cylindrical lockset, a mortised lockset, a multi-point lockset, arim exit device, a deadbolt, or another suitable mechanism.

FIG. 5 illustrates gasket 538 and a dry side of a door panel 518configured in accordance with one or more aspects of this disclosure. Alow threshold liquid containment door is described herein.

The liquid containment door is designed in such a way that gasket 538 isinstalled onto the dry side of door panel 518 to make a continuouslength of gasket (whether one piece, or multiple pieces connected) tocreate a liquid-tight seal between the door and the threshold (e.g.,threshold 736 of FIG. 7), and between the door and frame strike side 402and frame hinge side 404, up to the designed water protection level.

Door systems as described herein can function as a normal use “walkdoor,” however it may also perform as a flood barrier, spill containmentbarrier, or any other liquid containment system with a similar functionwhen the door is in the closed position. Latching can consist of anymechanism that will hold the door in the closed position. Latching typescan vary widely and can include standard commercial locksets and can becombined with door closers so that the door panel automatically swingsand latches into the closed position. Other methods of latching mayrequire manual engagement of devices that latch or further compress thegaskets to prepare the barrier for liquid containment. In addition to aliquid barrier, other requirements of typical “walk doors” can includeany or none of the following: egress doors, panic doors, fire rateddoors (e.g., fire-proof or doors graded to withstand certaintemperatures), tornado rated doors (e.g., doors graded to withstandcertain levels of force caused by a tornado), hurricane rated (e.g.,doors graded to withstand certain levels of force caused by wind and/orhurricanes), sound rated doors (e.g., doors graded to block sound up toa certain decibel level), water intrusion rated (e.g., doors graded toblock certain levels of water), and air infiltration rated (e.g., doorsgraded to have an airtight seal).

A continuous length of gasket (e.g., gasket 538) around the perimeter ofa flood harrier allows a liquid-tight seal to made more easily and ismore forgiving to field conditions and installation tolerances.Generally, there is a higher likelihood of water leakage anytime a floodgasket transitions over different materials or where multiple gasketsare joined together to create a liquid-tight seal. For example, a doorsystem that has a bottom horizontal gasket attached to the door paneland vertical gaskets installed onto the door frame requires precisealignment and overlap of conjoining gaskets and metal sealing surfacesso that the liquid-tight seal can be made when the door is closed. Usinga continuous length of gasket around the perimeter of the flood barriercreates a more simple and repeatable liquid-tight seal, especially ifthe gasket is installed on a planar surface (like a door panel surface)and seals to the surface of the door frame and threshold that are alsoaligned in a plane.

In some instances, in addition to, or in place of, gasket 538 installedon door panel 518, the frame and threshold gasket contact surfaces canbe modified to have sealants or rubber type materials such as gaskets toimprove the sealing surface for liquid-tightness. This can be especiallyuseful for increasing the liquid-tightness in areas where the gasketsealing surface transitions from one part to another, such as thethreshold to the vertical frame.

Gasket 538 provides multiple benefits over previous liquid containmentsystems. For instance, rather than use a bottom gasket situated on thedoor panel and remaining perimeter gaskets located on the frame, acontinuous gasket as described herein removes the joints formed by themultiple gasket pieces coming together as the door is closed andbreaking when the door is open. Further, rather than have the gasketinstalled to the frame and threshold that create a seal to the doorpanel, attaching the continuous gasket to the door panel removes theneed for the gasket to extend into the walk space of the door. Even ifthe gasket does not extend into the walk space of the door, placing thegasket in the area (e.g., on the threshold) where traffic moves throughmeans that wheels (such as those on wheelchairs or carts) and feet couldhit the threshold as objects move through the space, causing wear, andtherefore reducing the quality and effectiveness, of the gasket.Further, the continuous gasket described herein has the additionalbenefit of working with regulatory (ADA) Wheelchair accessibilitystandards, combining the benefits of a liquid-tight door system with theaccessible compliant door systems.

Also, unlike some other vertically hinged door products, the door systemdescribed herein does not require the bottom gasket to move downwardinto place to seal to a horizontal ground surface or small verticallyraised surface. In such other systems, this is often achieved by movingthe entire door panel downward to create downward pressure oncompression gaskets or by implementing inflatable gaskets that increasein size and expand downward to seal downward to a flush or lowthreshold. Inflatable gaskets often require methods of operation thatinclude air compressors or latching such as spin knobs and/or lockingdogs. Known drawbacks of inflatable gaskets include cost, maintenancerequirements, lifespan, and potential for catastrophic failures.

In accordance with the techniques and objects described herein, thecontinuous gaskets seal without the need for inflatable gaskets or thevertical movement of gaskets and/or the door panel. As such, thetechniques and objects described herein provide an opening that meetslow threshold dimensional requirements and overall height requirements,such as ADA wheelchair compliance standards or the United Kingdomequivalent (e.g., less than ¼ inch, ½ inch, ¾ inch, or 20 millimeters).The door described herein can act as a normal use door such as a typicalpedestrian door for interior or exterior applications. The doordescribed herein can also act as a passive flood barrier or manual floodbarrier, depending on the type of lockset and door hardware.

The thresholds and gasket systems described herein may be compatiblewith other threshold height requirements, as well. For instance,Finland, Germany, France, and the Netherlands all state they allow amaximum threshold height of 20 millimeters to be handicap-accessible.The United. Kingdom has a maximum threshold height of 15 millimeters.Canada states a maximum threshold height of 13 millimeters, and theUnited States provides a maximum threshold height of ½ inch. Thetechniques and door systems described herein may be compatible with anyof these requirements. Door thresholds may also be referred to as doorsills and/or door saddles.

FIG. 6 illustrates gasket 638 attached to door panel 618 and configuredin accordance with one or more aspects of this disclosure. As shown inFIG. 6, door panel 618 includes dry side panel 644, which may besituated on the side of door panel 618 facing the environment that is tobe protected from flood, spill, or other liquid conditions. Door panel618 also includes wet side panel 642, which may be situated on the sideof door panel 618 facing the environment that potentially contains theliquid to be protected against.

In the example of FIG. 6, the edge of door panel 618 has door edgeflange 640 that gasket 638 is attached to or located adjacent to. Gasket638 may be made of any material suitably configured to provide the levelof compression needed to create a liquid-tight seal, such as rubber,plastic, or any other resilient, waterproof material. Gasket 638 can beattached to door panel 618 such that water cannot fill the inside ofdoor panel 618 and cause mold, mildew, saturate insulation, or causecorrosion. Gasket 638 can be positioned such that any liquid wouldencounter gasket 638 before encountering any seams in door panel 618. Ifwater from flood waters penetrates the interior of door panel 618, thewater pressure can create additional stresses on the structure of doorpanel 618, meaning that a more robust door panel structure is required.Gasket 638 reduces the need to manufacture a fully sealed door panel(often by seal welds, sealant, epoxy) to prevent liquid intrusion in thepanel or further leakage through the entire barrier since theconstruction seams of the panel are not subjected to liquid pressure.

In some examples, liquid loads (e.g., hydrostatic, hydrodynamic and/orwave loading) on door panel 618 can be transferred to the door frame bydirect bearing of a region of door panel 618 that is not at or directlyadjacent to the gasket installation surface of door panel 618. Someliquid loading is still resisted by the hinge and gasket compressionforces, but most loading is transferred to the “door stop” surface (seestop surface 216 of FIG. 2A) of the frame from the structural panelstructure. Door panel 618 can transfer loading to the door frame in away that limits the amount of force or compression on gasket 638, thuslimiting the force transferred to the gasket attachment surface to limitthe structural requirements of the gasket attachment surface. In otherwords, the attachment of gasket 638 to the door edge flange 640 of doorpanel 618 allows door edge flange 640 to be manufactured of a lighterduty material. In some instances, door edge flange 640 is created by acontinuation of the wet side surface of door panel 618. In someinstances, the wet side of door panel 618 is made of sheet metal and isextended outwardly from door panel 618 to create the wet side of dooredge flange 640. In another example, door flange 640 can be created byhemming the portion of sheet metal extending from the edges of doorpanel 618 to create door edge flange 640 with a smooth, radiused edge.In instances where the full water loads of door panel 618 aretransferred through door edge flange 640, door edge flange 640 should bemade much more structural, which may be less economical and lessaesthetically acceptable for applications where the door system mustperform as a pedestrian door.

Gasket 638 can be installed on door edge flange 640 of the door that isrecessed from dry side panel 644 so that door edge flange 640 us moreprotected from damage and more aesthetically pleasing. In the case offire-rated doors, the recessed nature of gasket 638 may make the doorsmore likely to pass the UL10C fire test criteria by preventing exposedflaming of the gaskets to the non-fire side of the door panel. As thedoor swings closed, the location of gasket 638 close to the wet sidepanel 642 allows gasket 638 to move at a more perpendicular movementtowards the opposing frame sealing surface of the door frame. Thisallows better forward compression of gasket 638 rather than gasket 638rolling or sliding into position laterally. The hinge pivot positionadditionally contributes to this function.

In the case of gaskets that have a bulb-type closed section profile(e.g., the gasket is hollow in center), all or portions of gasket 638can optionally be fabricated with holes 670 through the core wall ofgasket 638 and allow air or water to move freely from the wet-side ofgasket 638 to the inner hollow core of gasket 638. Holes 670 can bealong the length of gasket 638 (e.g., 6 inches on center, 9 inches oncenter, 12 inches on center, or any other spacing) or can be in the formof a single or multiple holes (e.g., a slit, a notch, an open end ofgasket, or any other means of allowing passage of liquid freely frominside and out of the gasket hollow core to the “wet-side” of a liquidbarrier door). This allows flood water to enter the inside of gasket 638and exert hydrostatic pressure (equivalent to the flood water depthhydrostatic pressure) on the inside of gasket 638 towards the opposingframe sealing surface.

If a gasket design has a bulb-type profile (the gasket is hollow in themiddle), then holes drilled through the gasket wall into the hollow corecan allow water to enter the hollow core of the gasket. The waterpressure can press the gasket onto its sealing surface. The bulb-typegasket can have more lateral stability when loaded by water and betterforming characteristics when installing around corners of a door panel(e.g., less puckering). When liquid fills the hollow core of a bulb-typegasket through the holes, that liquid can neutralize the pressureapplied by liquid outside the gasket's hollow core, which cansignificantly reduce crushing or crumpling. When a door panel is beingclosed for the purpose of acting as a liquid barrier, the gasket mayallow air to escape from its hollow internal core through the vent holeswhen it is compressed between the door and frame, which allows thegasket to achieve more initial compression deflection. Initial gasketcompression is generally achieved by the swinging momentum of a doorthat compresses the gasket and automatically latches into the closedposition or by a manual method of engaging latching that creates initialgasket compression by drawing the door closer to the frame such asspin-knob latches, or quarter-turn latches. Initial gasket compressionis the compression of the gasket that is required to allow the door toact as a liquid containment barrier prior to liquid loads furthercompressing the door panel into the door frame. Initial gasketcompression is one of the largest challenges of creating a liquid-tightdoor when latching methods are limited to standard commercial doorclosers and locksets, where the door swing momentum must compressgasketing and latch the door closed without additional humanintervention (e.g., creating a “passive” flood barrier).

Gaskets can take various forms. As noted, the gasket can be a bulb-typedesign. In some instances, the gasket can be solid, with no hollow core.In some examples, the gasket can be made of dense rubber or foam.Gaskets can be extruded to have various cross-sectional profiles.

FIG. 7 illustrates a door system that includes door panel 718, gasket738, and threshold 736, each configured in accordance with one or moreaspects of this disclosure. Door panel 718 may be similar to any of, andmay be constructed of a similar material as, any of door panels 318,418, 518, and/or 618. In the example of FIG. 7, door panel 718 includesdoor edge flange 740 that extends from the edges of door panel 718.Gasket 738 can be attached to door edge flange 740 or attached to doorpanel 718 in a way that allows gasket 738 to be located adjacent to dooredge flange 740.

Threshold 736 is attached to a floor surface via frame base 712, whichprovides the template for drilling anchor bolts 730 through threshold736 and frame base 712 and into the floor surface. In this way,threshold 736 is secured to the floor surface and provides thresholdsealing surface 746 for the purpose of creating the liquid-tight seal.For instance, when door panel 718 is in the closed position, gasket 738comes into contact with and exerts force on threshold sealing surface746 above threshold base 748, as well as the frame sealing surfaces ofthe door frame. This continuous area of contact with adequate pressurecreates the liquid-tight seal in accordance with the techniques of thisdisclosure. Threshold sealing surface 746 can be any portion ofthreshold 736. In many examples, there may be a clear demarcationbetween threshold base 748 and threshold sealing surface 746. In otherexamples, threshold sealing surface 746 will be part of threshold base748.

Threshold 736 may be made of any material durable to handle foottraffic, wheel traffic, or any other traffic that may pass overthreshold 736. For instance, threshold 736 may be made of aluminum, butmay also be made of any other suitable material, such as wood, plastic,rubber, or any combination thereof. Threshold 736 may also include ribsor grooves, to increase the friction of threshold 736 and to reduce anyslipping that may occur from stepping on threshold 736.

FIGS. 8A-8B illustrate a door system that includes a door panel 818, acontinuous gasket 838, and a threshold 836, each configured inaccordance with one or more aspects of this disclosure. Gasket 838 anddoor panel 818 may be installed as part of a door system as describedelsewhere in this disclosure, such as the door systems of FIGS. 1-7. Assuch, reference may be made to the door systems of FIGS. 1-7 indescribing the environment in which gasket 838 and door panel 818 areinstalled.

In each of FIGS. 8A-8B, door panel 818, similar to previous door panelsdescribed herein, includes dry side panel 844 and wet side panel 846.Door panel 818 also includes door edge flange 840, which gasket 838 isattached to. Threshold 836 is attached to floor surface 808 via sealant850 and anchor bolt 830. Anchor bolt 830 is threaded through threshold836 and frame base 812 to secure each of threshold 836 and frame base812 to floor surface 808. Threshold 836 provides threshold sealingsurface 866 for the purpose of creating the liquid-tight seal. Forinstance, when door panel 818 is in the closed position, gasket 838comes into contact with and exerts force on threshold sealing surface866 above threshold base 848, as well as the frame sealing surfaces ofthe door frame. This continuous area of contact with adequate pressurecreates the liquid-tight seal in accordance with the techniques of thisdisclosure.

In accordance with the techniques described herein, a pedestrian doorsystem includes door frame 100 comprising frame strike side 402, framehinge side 404, and frame sealing surface 214 that extends at leastpartially up each of frame strike side 402 and frame hinge side 404. Inother words, frame sealing surface 214 is a bottom portion of framestrike side 402 and frame hinge side 404 that starts at the bottommostedge of frame strike side 402 and frame hinge side 404 and extendsupwards to the level at which the door system is intended to provide aliquid-tight seal. This may be some number of inches, feet, or theentirety of frame strike side 402 and frame hinge side 404.

The pedestrian door system also includes threshold 836 configured toextend between frame strike side 402 and frame hinge side 404. Threshold836 includes threshold base 848 configured to be secured to floorsurface 808 and threshold sealing surface 866. In some instances,threshold 836 has an overall height 856 from the floor surface 808 tothe uppermost surface of the threshold 836 (irrespective of any bevelededges) of no greater than 20 millimeters. In other instances, threshold836 may have an overall height 856 that is greater than or less than 20millimeters. Threshold 836 may have an overall height 856 that is nogreater than ¾ inch. In other instances, threshold 836 may have anoverall height 856 of no greater than ½ inch. In still other instances,threshold sealing surface 866 may extend upwardly from threshold base848 by a vertical distance 854 of no greater than ¼ inch. Thresholdsealing surface 866 may either extend vertically from threshold base 848or at a sloped angle.

In some instances, threshold 836 may be configured to reduce trippinghazards and make wheelchair access easier by having a sloped or taperedprofile (e.g., FIG. 8B). In some examples, the upper corners ofthreshold 836 may be rounded, beveled, or sloped at a certain ratio tocreate a gradual transition for traffic passing perpendicularly over thethreshold.

In some instances, all portions of threshold 836 that extend more than apredetermined height (e.g., ¼ inch) above floor surface 808 may have arise:run ratio or maximum slope ratio such that the upper portion ofthreshold 836 does not rise too steeply and pose a tripping hazard orimpede wheelchair traffic. In instances where portions of threshold 836that extend more than the predetermined height above floor surface 808(e.g., greater than ¼ inch) are not beveled, the surfaces can be setback from the lower adjacent surface of threshold 836 so that theoutermost profile of the threshold does not rise any steeper than acertain slope. Referring to threshold sealing surface 866 in FIG. 8A,the rise is shown as vertical distance 854, and the run is shown ashorizontal distance 860. In many instances, the rise:run ratio (e.g.,the ratio of vertical distance 854 to horizontal distance 860) can be nogreater than 1:2.

In some instances, the overall height of threshold 836 can be verticallyadjustable. For example, during installation of the door system, shims837 in threshold 836 can be positioned under threshold 836 to accountfor uneven floors. Vertical adjustment of threshold 836 may also ensureprecise alignment of gasket 838 and threshold 836 to ensure propergasket compression and overlap on threshold sealing surface 866 (e.g., ¼inch surface) of threshold 836. Door panel 818 or door frame 100 can beadjusted vertically to enable precise positioning of gasket 838 ontothreshold 836. The door system can optionally use commercial doorhardware to allow the door system to function as a pedestrian door, orthe door system can use custom or non-typical latching to secure doorpanel 818 into the closed position.

The door system may further include additional gaskets positionedelsewhere on door frame 100 and/or threshold 836 in order to furtherimprove the seal provided by gasket 838. For instance, frame sealingsurface 214 of frame strike side 402 and frame hinge side 404 of doorframe 100 may include a frame gasket, and/or threshold sealing surface866 of threshold 836 may include a threshold gasket.

In some example door systems disclosed herein, the threshold may notneed to comply with the handicap accessible standards discussedelsewhere herein. For various reasons, such thresholds need not qualifyas low thresholds for purposes of such regulations. In some suchexamples, the door system may be a cutout in a wall, and the threshold836 may be secured to the lower edge of the cutout.

In the example of FIG. 8A, threshold sealing surface 866 is shown as aflat sealing surface, creating approximately a right angle (e.g.,between 85 and 95 degrees) with floor surface 808. In some examples,threshold sealing surface 866 may form a different angle with floorsurface 808. For instance, in the example of FIG. 8B, threshold sealingsurface 866 is shown with a sloped surface. In other examples, thethreshold may be rounded, crowned, ribbed, or formed in any othersuitable shape.

The pedestrian door system also includes door panel 818 (which may besimilar to door panel 318 of FIG. 3), which includes panel bottom side820, panel strike side 322, panel hinge side 324, and gasket 838. Gasket838 extends continuously along panel bottom side 820 and at leastpartially up each of panel strike side 322 and panel hinge side 324. Insome instances, gasket 838 may extend between 3 feet and 8 feet up eachof panel strike side 322 and panel hinge side 324. Gasket 838 may beeither a one-piece gasket or multiple gasket segments contacting oneanother (e.g., bonded together). Gasket 838 may also be a bulb-typegasket with holes defined in a wet side wall of the continuous gasket.In such examples, the holes in gasket 838 are configured to receiveliquid and/or air into an interior space within gasket 838. In someconfigurations, the gasket ends may not be open in the contained liquid.The gasket ends may be closed, or the open gasket ends may be above thecontained liquid. In these configurations, the gasket interior isaccessible only through the holes.

In instances in which gasket 838 is a bulb-type gasket with holesdefined in the wet side wall, the gasket 838 may be attached to the doorframe and threshold rather than to the door panel 818. Gasket 838 may beattached to the door frame along the frame sealing surface and to thethreshold along the threshold sealing surface 866. In such instances,gasket 838 may also be continuous.

As shown in FIGS. 8A and 8B, door panel 818 consists of a main panel anddoor edge flange 840. In such instances, door edge flange 840 extendsoutwardly from door panel 818. The amount that door edge flange 840extends from door panel 818 may vary, as may the thickness of door edgeflange 840. Gasket 838 is then located adjacent to door edge flange 840,such as by being connected to door edge flange 840 or by being installedwithin a small distance from door edge flange 840 on panel bottom side320 (e.g., within 5 millimeters).

Door panel 818 may include dry side panel 844 and wet side panel 846. Insuch instances, door edge flange 840 may extend outwardly from wet sidepanel 846. Door edge flange 840 may extend toward dry side panel 844(e.g., less than 15% of the distance from wet side panel 846 to dry sidepanel 844, more than 50% of the distance from wet side panel 846 to dryside panel 844, etc.). In some examples, door edge flange 840 may extendoutwardly from door panel 818, not at wet side panel 846, but somewherebetween dry side panel 844 and wet side panel 846 (e.g., midway betweendry side panel 844 and wet side panel 846). Gasket 838 may then extendfrom door edge flange 840 toward dry side panel 844 of door panel 818.When flood water is pressing against wet side panel 846, dry side panel844 presses against the stop surface of the door frame. That reducesforces on door edge flange 840 so that door edge flange 840 can beconstructed in a less robust manner. For example, wet side panel 846 maycomprise a sheet of metal that is hemmed to create door edge flange 840.

FIGS. 9A-9C show a door hinge 902 that can be used in illustrativepedestrian door systems. Door panel 918 includes door edge flange 940,which gasket 938 is attached to. Gasket 938 may be a bulb-type gasket,which includes hollow space 966. Threshold 936 is attached to a floorsurface and frame base 912 with anchor bolt 930.

The door system described herein may use a custom aluminum geared hingethat fastens to the frame and the wet-side face of the door panel. Doorhinge 902 can be a geared hinge configured to hingedly couple panelhinge side 920 of door panel 918 to frame hinge side 904 of the doorframe. In some examples, the door hinge can be a piano hinge, a barrelhinge, or other suitable hinge. The door hinge 902 facilitates hingedmovement of door panel 918 relative to the door frame between an openposition and a closed position. When door panel 918 is in the closedposition, gasket 938 is positioned between panel sealing surface 919 ofdoor panel 918 and frame sealing surface 914 of frame strike side andframe hinge side 904 of the door frame to create a liquid-tight seal.When door panel 918 is in the closed position, gasket 938 is alsopositioned between the panel sealing surface (819 of FIG. 8A) and thethreshold sealing surface (866 of FIG. 8A) of the threshold (836 of FIG.8A) to create a liquid-tight seal.

In some instances, the door hinge 902 has a hinge leaf 958 that extendsbeyond door edge flange 940 and attaches to door panel 918. This hingeleaf 958 may also be a flexible hinge leaf. Door hinge 902 may beconfigured to facilitate hinged movement of door panel 918 relative tothe door frame about a hinge axis (vertical) that is located outwardlyfrom an outermost extent of door panel 918 by a particular distance. Insome examples, that hinge offset 960 may be at least ⅝ inch. Door hinge902 can be a surface mount hinge or a geared hinge or other hinge thatfastens to wet side panel 946 and a wet side 948 of the door frame. Thestationary portion of door hinge 902 may be attached to the wet side ofdoor frame, and the hinge leaf 958 may extend some distance (generallyparallel to the surface of door panel 918). The length and orientationof the hinge leaf 958 may allow liquid pressure on door panel 918 todeflect door panel 918 further into the door frame to increasecompression of gasket 938 compression and can allow dry side panel 944to contact the stop surface 916. Hinge leaf 958 may extend beyond dooredge flange 940 so that hinge fasteners can be attached to the main doorstructure of door panel 918 rather than to door edge flange 940.

Door hinge 902 may be configured to facilitate hinged movement of doorpanel 918 relative to the door frame about hinge pivot 962. Hinge pivot962 is located in a position such that, as door panel 918 moves into theclosed position, gasket 938 moves more perpendicularly to frame sealingsurface 914. If hinge pivot 962 were located. closer to gasket 938,gasket 938 may roll into frame sealing surface 914 or compress laterallyinto frame sealing surface 914 rather than in being pressed onto framesealing surface 914. Hinge pivot 962 may have a vertical axis.

The process of moving door panel 918 from the closed position to theopen position is shown in the sequence of FIGS. 9A-9C. In the example ofFIG. 9A, door panel 918 is in the closed position. In some examples,when door panel 918 is in the closed position, the wet side 950 of dooredge flange 940 and wet side panel 946 may be within 1/16 inch of flushwith wet side 948 of the door frame. In FIG. 9B, door panel 918 beginsto open as hinge leaf 958 and door panel 918 rotate around hinge pivot962. In FIG. 9C, door panel 918 is in the open position, with hingepivot 962 extending door panel 918 away from the frame, protecting theframe and gasket 938. Looking at FIG. 9C, then FIG. 9B, then FIG. 9Ashows door panel 918 swinging into the closed position.

When door panel 918 is in the closed position, the flexible hinge leaf958 is configured to allow movement of door panel 918 relative to thedoor frame (perpendicular to door panel surface) when pressure isapplied to wet side panel 946. This is particularly advantageous at thehinge-side of the door system where this feature allows additionalgasket compression to be achieved with increasing amounts of pressure ondoor panel 918.

In some instances, the door frame includes stop surface 916 that isseparate from frame sealing surface 914. In such instances, when doorpanel 918 is in a closed position, dry side panel 944 is adjacent tostop surface 916. As liquid presses on wet side panel 946, dry sidepanel 944 presses against stop surface 916. Such pressures need not beborne by the door edge flange or by the hinge components, which isbeneficial in examples involving a more rigid hinge (e.g., a butthinge).

Example door systems include door hinges that allow for hinged movementof the door panel relative to the door frame between open and closedpositions. In some instances, the door hinge may be configured tohingedly couple a side of the door panel to the door frame. In suchinstances, the door panel may move between open and closed positionsabout a vertical hinge axis. In some instances, the door hinge may beconfigured to hingedly couple the bottom of the door panel to the doorframe. In such instances, the door panel may move between open andclosed positions about a horizontal hinge axis.

FIG. 10 illustrates geared hinge 1064 and door frame 1000 of a doorsystem configured in accordance with one or more aspects of thisdisclosure. The length, material, and thickness of hinge leaf 1058 thatextends onto wet side panel 1044 is designed so that liquid pressure onthe door can flex the hinge material so that the door system is able toachieve increased gasket compression as liquid levels rise higher on thedoor. Hinge pivot 1062 and hinge leaf 1058 can rebound after floodconditions recede without resulting in permanent deflection or damage togeared hinge 1064.

The pedestrian door system may also be a double door system. FIG. 11illustrates a door system that includes two door panels 1118A and 1118B,center post 1170, and door frame 1100, each configured in accordancewith one or more aspects of this disclosure. Each of door panels 1118Aand 1118B may be similar to, and may be constructed of similar materialsas, any of door panels described herein.

Door frame 1100 may include openings for each of door panels 1118A and1118B. Door frame 1100 may comprise frame strike sides on each side ofcenter post 1170. Door frame 1100 may include first frame hinge side1126A, and a first frame sealing surface that extends at least partiallyup each of the first side of center post 1170 and first frame hinge side1126A. Door frame 1100 may also include second frame hinge side 1126Band a second frame sealing surface that extends at least partially upeach of another side of center post 1170 and second frame hinge side1126B.

The door system may include two thresholds with characteristics likethose of other thresholds described herein. The door system may includefirst threshold 1136A, which extends between the first side of centerpost 1170 and first frame hinge side 1126A. First threshold 1136Aincludes a base configured to be secured to a floor surface and athreshold sealing surface. The door system can include second threshold1136B configured to extend between center post 1170 and second framehinge side 1126B, with second threshold 1136B having dimensions likethose of first threshold 1136A.

As noted, first door panel 1118A and second door panel 1118B may besimilar to other door panels described herein. First door panel 1118Amay include first panel bottom side 1120A, first panel strike side1122A, first panel hinge side 1124A, and a continuous gasket extendingcontinuously along first panel bottom side 1120A and at least partiallyup each of first panel strike side 1122A and first panel hinge side1124A. Second door panel 1118B may include second panel bottom side1120B, second panel strike side 1122B, second panel hinge side 1124B,and a second continuous gasket extending continuously along second panelbottom side 1120B and at least partially up each of second panel strikeside 1122B and second panel hinge side 1124B.

The door system may include first and second hinges. The first hinge maybe configured to hingedly couple first panel hinge side 1124A of firstdoor panel 1118A to first frame hinge side 1126A of door frame 1100. Thefirst door hinge can facilitate hinged movement first door panel 1118Arelative to door frame 1100 between an open position and a first closedposition. When in the first closed position, the continuous gasket offirst door panel 1118A seals against the frame sealing surface of doorframe 1100 and against the threshold sealing surface of the threshold ina liquid-tight manner. The second hinge may be configured to hingedlycouple second panel hinge side 1124B of second door panel 1118B tosecond frame hinge side 1126B of door frame 1100. The second door hingecan facilitate hinged movement of second door panel 1118B relative todoor frame 1100 between a second open position and a second closedposition. When in the second closed position, the continuous gasket ofsecond door panel 11189 seals against the second frame sealing surfaceof door frame 1100 in a liquid-tight manner.

It is to be recognized that depending on the example, certain acts orevents of any of the techniques described herein can be performed in adifferent sequence, may be added, merged, or left out altogether (e.g.,not all described acts or events are necessary for the practice of thetechniques). Various examples of the disclosure have been described. Anycombination of the described systems, operations, or functions iscontemplated. These and other examples are within the scope of thefollowing claims.

What is claimed is:
 1. A pedestrian door system comprising: a door framecomprising a frame strike side, a frame hinge side, and a frame sealingsurface that extends at least partially up each of the frame strike sideand the frame hinge side; a threshold configured to extend between theframe strike side and the frame hinge side, the threshold including abase configured to be secured to a floor surface and a threshold sealingsurface, wherein the threshold has an overall height of no greater than½ inch; a door panel comprising a panel bottom side, a panel strikeside, a panel hinge side, and a continuous gasket extending continuouslyalong the panel bottom side and at least partially up each of the panelstrike side and the panel hinge side; and a door hinge configured tohingedly couple the panel hinge side of the door panel to the framehinge side of the door frame and to facilitate hinged movement of thedoor panel relative to the door frame between an open position and aclosed position in which the continuous gasket of the door panel sealsagainst the frame sealing surface of the door frame and against thethreshold sealing surface of the threshold in a liquid-tight manner. 2.The pedestrian door system of claim 1, wherein the door frame furthercomprises a frame top side, and the frame sealing surface extends alongan entirety of the frame strike side, the frame top side, and the framehinge side, and wherein the door panel further comprises a panel topside, and the continuous gasket extends continuously along the entiretyof the panel strike side, the panel top side, the panel hinge side, andthe panel bottom side.
 3. The pedestrian door system of claim 1, whereinthe continuous gasket extends between 3 feet and 8 feet up each of thepanel strike side and the panel hinge side.
 4. The pedestrian doorsystem of claim 1, wherein all portions of the threshold configured toextend at least ¼ inch above the floor surface have a rise:run ratio ofno greater than 1:2.
 5. The pedestrian door system of claim 1, whereinthe threshold sealing surface extends upwardly from the base by avertical distance of no greater than ¼ inch.
 6. The pedestrian doorsystem of claim 5, wherein the threshold sealing surface extendsvertically from the base.
 7. The pedestrian door system of claim 1,wherein the overall height of the threshold is vertically adjustable. 8.The pedestrian door system of claim 1, wherein the door panel furthercomprises a main panel and a door edge flange, the door edge flangeextending outwardly from the main panel, wherein the continuous gasketis located adjacent to the door edge flange.
 9. The pedestrian doorsystem of claim 8, wherein the main panel includes a dry side and a wetside, the door edge flange extending outwardly from the wet side of themain panel, and the continuous gasket extending from the door edgeflange toward the dry side of the main panel.
 10. The pedestrian doorsystem of claim 9, wherein the door edge flange includes a wet side, andwherein the wet side of the door edge flange and the wet side of themain panel form a continuous, uninterrupted planar surface.
 11. Thepedestrian door system of claim 10, wherein the wet side of the mainpanel comprises a sheet of metal that is hemmed to create the door edgeflange.
 12. The pedestrian door system of claim 9, wherein the wet sideof the door edge flange and the wet side of the main panel are within1/16 inch of flush with a wet side of the door frame when the door panelis in the closed position.
 13. The pedestrian door system of claim 8,wherein the door frame comprises a stop surface that is separate fromthe frame sealing surface, and wherein a dry side of the door panel isadjacent to the stop surface when the door panel is in the closedposition.
 14. The pedestrian door system of claim 8, wherein the doorhinge comprises a hinge leaf that extends beyond the door edge flangeand attaches to the main panel.
 15. The pedestrian door system of claim1, wherein the door hinge comprises a flexible hinge leaf.
 16. Thepedestrian door system of claim 1, wherein the continuous gasketcomprises a one-piece gasket.
 17. The pedestrian door system of claim 1,wherein the continuous gasket comprises multiple gasket segmentscontacting one another.
 18. The pedestrian door system of claim 1,wherein no gasket is attached to the threshold sealing surface.
 19. Thepedestrian door system of claim 1, wherein the continuous gasketcomprises a bulb-type gasket with holes defined in a wet side wall ofthe continuous gasket, the holes being configured to receive liquidand/or air into an interior space within the bulb-type gasket.
 20. Thepedestrian door system of claim 1, wherein the door hinge is configuredto facilitate hinged movement of the door panel relative to the doorframe about a hinge axis that is located outwardly from an outermostextent of the door panel by at least ⅝ inch.
 21. The pedestrian doorsystem of claim 1, wherein the frame sealing surface of the door framecomprises a frame gasket and/or the threshold sealing surface of thethreshold comprises a threshold gasket.
 22. The pedestrian door systemof claim 1, further comprising a passive latching mechanism configuredto hold the door panel in the closed position without separate manualactivation.
 23. The pedestrian door system of claim 1, wherein the framestrike side includes a center post, the frame sealing surface extendingat least partially up one side of the center post, the door frameincluding a second frame hinge side and a second frame sealing surfacethat extends at least partially up each of another side of the centerpost and the second frame hinge side, and wherein the pedestrian doorsystem further comprises: a second threshold configured to extendbetween the center post and the second frame hinge side, the secondthreshold having dimensions like those of the threshold, a second doorpanel comprising a second panel bottom side, a second panel strike side,a second panel hinge side, and a second continuous gasket extendingcontinuously along the second panel bottom side and at least partiallyup each of the second panel strike side and the second panel hinge side,and a second door hinge configured to hingedly couple the second panelhinge side of the second door panel to the second frame hinge side ofthe door frame and to facilitate hinged movement of the second doorpanel relative to the door frame between a second open position and asecond closed position in which the second continuous gasket of thesecond door panel seals against the second frame sealing surface of thedoor frame in a liquid-tight manner.
 24. A door system comprising: adoor frame comprising a frame first side, a frame second side, and aframe sealing surface that extends at least partially up each of theframe first side and the frame second side; a threshold configured toextend between the frame first side and the frame second side, thethreshold including a base configured to be secured to a surface, andthe threshold further including a threshold sealing surface; a doorpanel comprising a panel bottom side, a panel first side, a panel secondside, and a panel sealing surface that extends along the panel bottomside and at least partially up each of the panel first side and thepanel second side; and a gasket that comprises a bulb-type gasket withholes defined in a wet side wall of the gasket, the holes beingconfigured to receive liquid and/or air into an interior space withinthe bulb-type gasket, wherein the door panel is movable relative to thedoor frame between an open position and a closed position in which thegasket is positioned between the panel sealing surface of the door paneland the frame sealing surface of the door frame and between the panelsealing surface of the door panel and the threshold sealing surface ofthe threshold to create a liquid-tight seal.
 25. The door system ofclaim 24, wherein the gasket is attached to the door panel along thepanel sealing surface.
 26. The door system of claim 24, wherein thegasket is attached to the door frame along the frame sealing surface andto the threshold along the threshold sealing surface.
 27. The doorsystem of claim 24, wherein the gasket is continuous.
 28. The doorsystem of claim 24, further comprising a door hinge configured tohingedly couple the panel first side of the door panel to the framefirst side of the door frame and to facilitate hinged movement of thedoor panel between the open position and the closed position.
 29. Thedoor system of claim 24, further comprising a door hinge configured tohingedly couple the panel bottom side of the door panel to the thresholdand to facilitate hinged movement of the door panel between the openposition and the closed position.
 30. A door system comprising: a doorframe comprising a frame strike side, a frame hinge side, and a framesealing surface that extends at least partially up each of the framestrike side and the frame hinge side; a threshold configured to extendbetween the frame strike side and the frame hinge side, the thresholdincluding a base configured to be secured to a floor surface, and thethreshold further including a threshold sealing surface, wherein thethreshold has an overall height of no greater than ½ inch; a door panelcomprising a panel bottom side, a panel strike side, a panel hinge side,and a continuous gasket extending continuously along the panel bottomside and at least partially up each of the panel strike side and thepanel hinge side; and a door hinge configured to hingedly couple thepanel hinge side of the door panel to the frame hinge side of the doorframe and to facilitate hinged movement of the door panel relative tothe door frame between an open position and a closed position in whichthe continuous gasket of the door panel seals against the frame sealingsurface of the door frame and against the threshold sealing surface ofthe threshold in a liquid-tight manner.
 31. The door system of claim 30,wherein the door frame comprises a pedestrian door frame, and the doorpanel comprises a pedestrian door panel.
 32. The door system of claim30, wherein the threshold sealing surface extends upwardly from the baseby a vertical distance of no greater than ¼ inch.
 33. The door system ofclaim 32, wherein the threshold sealing surface extends vertically fromthe base.